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Issue description:

Minecraft Client crashes when you scroll to the Mekanism section of the mod items.

Steps to reproduce:

1. Load Mekanism
2. Scroll to Mekanism section of items in the creative menu
3. Crash...

Version (make sure you are on the latest version before reporting):

Forge: 1.12.2-14.23.4.2707
Mekanism: 1.12.2-9.4.10.345
Other relevant version: Tinkers Construct (TConstruct): 1.12.2-2.10.1.84
Full mod list: https://www.dropbox.com/sh/lllqnrha4dqibzz/AADWg9QoGvLDnIpEyUeLHhwGa?dl=1

If a (crash)log is relevant for this issue, link it here: (It's almost always relevant)

https://hastebin.com/aqojanulux.coffeescript

Problem solved. It's due to an incompatibility with ProjectRed-1.12.2-4.90.86-mechanical. Good to keep in mind for future modpacks.
You guys should create an incompatible document with all of the known incompatible mods. (Just a suggestion).
Issue closed.